1. Field of the Invention
The present invention relates to a process cartridge and an electrophotographic image forming apparatus. Here, the "electrophotographic image forming apparatus" is an apparatus for forming an image on a recording medium by using an electrophotographic image forming system. For example, the electrophotographic image forming apparatus may be an electrophotographic copying machine, an electrophotographic printer (for example, a laser beam printer or an LED printer), an electrophotographic facsimile or an electrophotographic word processor. The "process cartridge" incorporates therein an electrophotographic photosensitive member and at least one of a charge means, a developing means and a cleaning means as a cartridge unit which can detachably mounted to a main body of an electrophotographic image forming apparatus.
2. Related Background Art
A conventional electrophotographic image forming apparatus such as an electrophotographic copying machine, a laser beam printer or the like includes a photosensitive drum. Well-known processes such as charging, exposure and development is successively effected regarding the photosensitive drum, thereby forming a toner image on the photosensitive drum and transferring the toner image onto a recording medium. Thereafter, residual toner remaining on the photosensitive drum is removed by a cleaning device. In this way, the image is formed.
In such electrophotographic image forming apparatuses, recently, a process cartridge is adopted to make the apparatus compact and simplify the maintenance. In the process cartridge, the photosensitive drum and the process means (such as a charge member, a developing member and a cleaning member) acting on the photosensitive drum are integrally incorporated as a cartridge unit which can detachably mounted to a main body of the image forming apparatus by an operator himself.
In such a process cartridge, a cartridge frame is provided at its lower portion with an opening through which the photosensitive drum can be contacted with the recording medium being conveyed. In a condition that the process cartridge is dismounted from the main body of the image forming apparatus, by closing the opening by an open/close shutter member, the photosensitive drum is protected. The shutter member is normally connected to the cartridge frame via a connection member.